//单击可以在文本中显示,双击就只能显示一下,不能一直显示,请问是什么问题?
import java.awt.*;
import java.awt.event.*;
public class test10{
public static void main(String args[])
{
MyFrame f = new MyFrame();
f.setBounds(100,100,200,300);
f.setVisible(true);
f.validate();
f.addWindowListener(new WindowAdapter()
{ public void WindowClosing(WindowEvent e)
{
System.exit(0);
}
}
);
}
}
class MyFrame extends Frame implements ItemListener,ActionListener
{
List lst1;//列表框
TextArea area;
int count=1;
public MyFrame()
{
area=new TextArea(6,25);
lst1=new List(2,false);
lst1.add("苹果");
lst1.add("香蕉");
lst1.add("荔枝");
lst1.add("雪梨");
add(lst1,BorderLayout.NORTH);
add(area,BorderLayout.CENTER);
lst1.addItemListener(this);
lst1.addActionListener(this);
}
public void itemStateChanged(ItemEvent e)
{
if(lst1.getSelectedIndex()==0)
{
area.setText("苹果");
}
else if(lst1.getSelectedIndex()==1)
{
area.setText("香蕉");
}
else if(lst1.getSelectedIndex()==2)
{
area.setText("荔枝");
}
else if(lst1.getSelectedIndex()==3)
{
area.setText("雪梨");
}
}
public void actionPerformed(ActionEvent e)
{
if(e.getSource()==lst1)
if(lst1.getSelectedIndex()==0)
{
area.setText("\n"+lst1.getSelectedItem()+":红富士来至山东");
}
else if(lst1.getSelectedIndex()==1)
{
area.setText("\n"+lst1.getSelectedItem()+":海南香蕉来至海南");
}
else if(lst1.getSelectedIndex()==2)
{
area.setText("\n"+lst1.getSelectedItem()+":水晶荔枝来至广西");
}
else if(lst1.getSelectedIndex()==3)
{
area.setText("\n"+lst1.getSelectedItem()+":香甜雪梨来至四川");
}
}
}
import java.awt.*;
import java.awt.event.*;
public class test10{
public static void main(String args[])
{
MyFrame f = new MyFrame();
f.setBounds(100,100,200,300);
f.setVisible(true);
f.validate();
f.addWindowListener(new WindowAdapter()
{ public void WindowClosing(WindowEvent e)
{
System.exit(0);
}
}
);
}
}
class MyFrame extends Frame implements ItemListener,ActionListener
{
List lst1;//列表框
TextArea area;
int count=1;
public MyFrame()
{
area=new TextArea(6,25);
lst1=new List(2,false);
lst1.add("苹果");
lst1.add("香蕉");
lst1.add("荔枝");
lst1.add("雪梨");
add(lst1,BorderLayout.NORTH);
add(area,BorderLayout.CENTER);
lst1.addItemListener(this);
lst1.addActionListener(this);
}
public void itemStateChanged(ItemEvent e)
{
if(lst1.getSelectedIndex()==0)
{
area.setText("苹果");
}
else if(lst1.getSelectedIndex()==1)
{
area.setText("香蕉");
}
else if(lst1.getSelectedIndex()==2)
{
area.setText("荔枝");
}
else if(lst1.getSelectedIndex()==3)
{
area.setText("雪梨");
}
}
public void actionPerformed(ActionEvent e)
{
if(e.getSource()==lst1)
if(lst1.getSelectedIndex()==0)
{
area.setText("\n"+lst1.getSelectedItem()+":红富士来至山东");
}
else if(lst1.getSelectedIndex()==1)
{
area.setText("\n"+lst1.getSelectedItem()+":海南香蕉来至海南");
}
else if(lst1.getSelectedIndex()==2)
{
area.setText("\n"+lst1.getSelectedItem()+":水晶荔枝来至广西");
}
else if(lst1.getSelectedIndex()==3)
{
area.setText("\n"+lst1.getSelectedItem()+":香甜雪梨来至四川");
}
}
}
import java.awt.*;
import java.awt.event.*;
public class test10{
public static void main(String args[])
{
MyFrame f = new MyFrame();
f.setBounds(100,100,200,300);
f.setVisible(true);
f.validate();
f.addWindowListener(new WindowAdapter()
{ public void WindowClosing(WindowEvent e)
{
System.exit(0);
}
}
);
}
}
class MyFrame extends Frame implements ItemListener,ActionListener
{
List lst1;//列表框
TextArea area;
int count=1;
public MyFrame()
{
area=new TextArea(6,25);
lst1=new List(2,false);lst1.add("苹果");
lst1.add("香蕉");
lst1.add("荔枝");
lst1.add("雪梨");add(lst1,BorderLayout.NORTH);
add(area,BorderLayout.CENTER);
lst1.addItemListener(this);
lst1.addActionListener(this);
}
public void itemStateChanged(ItemEvent e)
{
if(count==1)//添加
{
if(lst1.getSelectedIndex()==0)
{
area.setText("苹果");
}
else if(lst1.getSelectedIndex()==1)
{
area.setText("香蕉");
}
else if(lst1.getSelectedIndex()==2)
{
area.setText("荔枝");
}
else if(lst1.getSelectedIndex()==3)
{
area.setText("雪梨");
}
}
else
count=1;
}
public void actionPerformed(ActionEvent e)
{
if(e.getSource()==lst1)
if(lst1.getSelectedIndex()==0)
{
area.setText("\n"+lst1.getSelectedItem()+":红富士来至山东");
}
else if(lst1.getSelectedIndex()==1)
{
area.setText("\n"+lst1.getSelectedItem()+":海南香蕉来至海南");
}
else if(lst1.getSelectedIndex()==2)
{
area.setText("\n"+lst1.getSelectedItem()+":水晶荔枝来至广西");
}
else if(lst1.getSelectedIndex()==3)
{
area.setText("\n"+lst1.getSelectedItem()+":香甜雪梨来至四川");
}}
count++;
}